The Metabolism and Pharmacokinetic of Rhein and Aurantio-obtusin

Background: The anthraquinones, rhein and aurantio-obtusin, were isolated from Duhaldea nervosa for the first time by our group, which also were first found at Compasitae. Anthraquinone compounds have a lot of pharmacological activities such as anti-inflammatory, anti-cancer, anti-oxidation, anti-diabetes, and can be used for laxative, liver protection, treatment of chronic renal failure, etc. But in recent years, anthraquinones have been reported to be cytotoxic to the liver and kidneys. Therefore, it is very important to study the pharmacokinetics and metabolism of rhein and aurantio-obtusin, which are common ingredients in many traditional Chinese medicine (TCM). The pharmacokinetics and metabolism of rhein and aurantio-obtusin for the first time were comprehensively summarized in the paper.

Objective: Providing a comprehensive information for pharmacokinetics and metabolism of rhein and aurantio-obtusin in different species, meanwhile, the aim of this review is also to provide a reference for reasonable application for TCM enriched these two ingredients.

Methods: The metabolism and pharmacokinetic of rhein and aurantio-obtusin were searched by the Web of Science, PubMed, Google scholar and some Chinese literature databases.

Results: Rhein and aurantio-obtusin exist mainly in the form of metabolites in the body. Rhein and aurantio-obtusin and its metabolites might be the material basis of its pharmacological effects in the body. Therefore, the significance of studying the in vivo metabolites of rhein and aurantio-obtusin is not only to clarify its pharmacological mechanism, but also to find new active compound ingredients. The metabolism of rhein is different in different species, so the toxicity differences after oral administration may be due to the species differences in rhein metabolism. But metabolic profiles for aurantio-obtusin in liver microsomes of different species are similar.

Conclusion: This paper not only provides the pharmacokinetics of rhein and aurantio-obtusin, but also facilitates further study the metabolism of rhein and aurantio-obtusin.

Keywords: Duhaldea nervosa; anthraquinones; aurantio-obtusin; metabolism; pharmacokinetics; rhein.